½ pound large white mushrooms, halved
½ pound green beans, trimmed
1 red onion, cut into 1⁄2-inch-thick rounds
3 tablespoons olive oil
kosher salt and black pepper
½ teaspoon granulated onion
1 pound whole portabella mushrooms
1 teaspoon granulated garlic
½ teaspoon rosemary, broken
½ teaspoon dried thyme
4 tablespoons balsamic vinegar
1 bunch salad burnet or watercress, thick stems removed (about 4 cups)
Heat grill to medium-high. In a large bowl, toss the white mushrooms, green beans, onion, 1 tablespoon oil, ½ teaspoon salt, and ¼ teaspoon pepper, ½ teaspoon granulated onion. Grill these marinated vegetables (place the beans perpendicular to the grates to keep them from falling through), turning occasionally, removing them as they become tender, 8 to 12 minutes.
Meanwhile, season the portobellas with garlic, herbs and ½ teaspoon salt and ¼ teaspoon pepper. Grill alongside the vegetables stem side down, brushing occasionally with 2 tablespoons vinegar, 3 to 5 minutes per side, until tender and nicely browned. Let rest for 5 minutes before slicing.
Divide the salad burnet / watercress, grilled vegetables, and sliced portabellas among bowls. Drizzle with the remaining 2 tablespoons oil and 2 tablespoons vinegar.